66545161656 has 64 divisors (see below), whose sum is σ = 168942257280. Its totient is φ = 21838185600.

The previous prime is 66545161621. The next prime is 66545161679. The reversal of 66545161656 is 65616154566.

It is a junction number, because it is equal to n+sod(n) for n = 66545161599 and 66545161608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3055606 + ... + 3077306.

It is an arithmetic number, because the mean of its divisors is an integer number (2639722770).

Almost surely, 2^66545161656 is an apocalyptic number.

It is an amenable number.

66545161656 is an abundant number, since it is smaller than the sum of its proper divisors (102397095624).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66545161656 is a wasteful number, since it uses less digits than its factorization.

66545161656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23684 (or 23680 counting only the distinct ones).

The product of its digits is 3888000, while the sum is 51.

The spelling of 66545161656 in words is "sixty-six billion, five hundred forty-five million, one hundred sixty-one thousand, six hundred fifty-six".